Q: Is 21,551 a Prime Number?
A: No, 21,551 is not a prime number.
A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 21551 can be evenly divided by 1 23 937 and 21,551, with no remainder.
Since 21,551 cannot be divided by just 1 and 21,551, it is not a prime number.